Reinforcing element for concrete structures

ABSTRACT

The invention is concerned with mat-like or plate-shaped elements such as are used as reinforcing elements and as shuttering in the production of concrete structures. These elements are generally somewhat flexible in character and when of large size or formed into an assembly of large size have hitherto had to be supported in their predetermined position until hardening of the concrete applied is completed. The reinforcing elements of the present invention are made substantially selfsupporting by the arrangement along at least one edge of a supporting element which is resistant to bending. Suitably the supporting element resistant to bending is a steel section applied to a reinforcing element which comprises parallel longitudinal ribs of rod-like steel connected by parallel striplike transverse ribs bent alternately in the one and other direction perpendicular to the plane of the plate.

United States Patent [191 Glatz [11] 3,786,610 4 1*Jan. 22 1974 REINFORCING ELEMENT FOR CONCRETE STRUCTURES [75] Inventor: Horst Glatz, Eldagsen Hanover,

Germany [73] Assignee: Deumu Deutsche Erz-und Metall-Union Gesellschaft mit beschrankter Haftung, Hanover, Germany Notice: The portion of the term of this patent subsequent to June 19, 1990, has been disclaimed.

[22] Filed: Dec. 3, 1971 [21] Appl. No.: 204,653

[30] Foreign Application Priority Data Dec. 17, 1970 Germany P 20 62 099.9

[5 6] References Cited UNITED STATES PATENTS 4/1879 Hennessey ..52/674 8/1904 Clark 52/671 1,704,608 3/1929 Humphris 52/671 1,897,842 2/1933 Herbest 52/670 2,148,698 2/1939 Lachman 52/670 Berman [57] ABSTRACT The invention is concerned with mat-like or plateshaped elements such as are used as reinforcing elements and as shuttering in the production of concrete structures. These elements are generally somewhat flexible in character and when of large size or formed into an assembly of large size have hitherto had to be supported in their predetermined position until hardening of the concrete applied is completed. The reinforcing elements of the present invention are made substantially self-supporting by the arrangement along at least one edge of a supporting element which is resistant to bending. Suitably the supporting element resistant to bending is a steel section applied to a reinforcing element which comprises parallel longitudinal ribs of rod-like steel connected by parallel strip-like transverse ribs bent alternately in the one and other direction perpendicular to the plane of the plate.

7 Claims, 5 Drawing Figures PATENTHJ JAN 2 P? SHEET 2 8F 2 REINFORCING ELEMENT FOR CONCRETE STRUCTURES This application discloses an improvement over the invention described in copending application, Ser. No. 124,826, filed by the same inventor on Mar. 16, 1971, and now issued on June 19, 1973 as US. Pat. No. 3,739,542.

BACKGROUND OF THE INVENTION Mat-like or plate-shaped reinforcing elements which can be filled with and/or sprayed over with concrete are used in the production of concrete structures. Such reinforcing elements can for example be used for the production of a supporting steel reinforced concrete structure in tunnels or mines and at the same time serve as lost shuttering for the concrete. These elements are in general readily flexible in elastic or plastic zones, since they or their component parts have only a slight thickness perpendicular to the plane of the plate. Large reinforcing elements and large assemblies of several reinforcing elements must accordingly be supported in their pre-calculated position for sufficient time until the surrounding concrete has hardened. Otherwise the reinforcing elements are deformed under the action of their own weight and take up a false position. An arrangement of several reinforcing elements can even collapse.

SUMMARY OF THE INVENTION It is an object of the invention to create a reinforcing element of the aforementioned type which alone or in combination with further similar reinforcing elements produces a self-supporting reinforcement.

According to the invention there is provided a matlike or plate-shaped reinforcement element, for use in the production of concrete structures, which can be filled with or sprayed over with concrete and is characterised in that a supporting element resistant to bending is arranged along at least one of its edges. Such a reinforcing element, or reinforcing or shuttering constructions composed of such reinforcing elements, do not require before hardening of theconcrete anysupporting devices, for example erection arches or erection framework. The individual reinforcing elements are prevented from deformation because of the supporting elements resistant to bending, so that the reinforcing elements maintain their original pre-calculated position after the erection without auxiliary measures. The omission of additional supporting means gives a consid' erable saving of labour in the production of the concrete structure. In tunnel construction an arch-shaped reinforcing and shuttering construction composed of reinforcing elements in accordance with the invention, forms in addition for the personnel working at the site a protection against falling rock before the appropriate tunnel section is coated with concrete and without an additional structure being required.

A preferred embodiment of the invention is characterised in that the supporting element resistant to'bending is formed as a steel section connected with the reinforcing element, the resistance to bending of the steel section transverse to the plane of the reinforcing element being at least as large as that parallel to the plane of the reinforcing element. Such steel sections are relatively cheap and can easily be applied, for example by welding, to the reinforcing element. All kinds of steel sections resistant to bending in at least one direction are applicable. Preferably a steel section is used as supporting element resistant to bending, the resistance to bending of the section or profile being greater transverse to the plane of'the reinforcing element than the resistance to bending of the rest of the reinforcing element in the same direction. In this case the steel section forms the supporting framework in a reinforcing or shuttering construction, the intermediate spaces of which are furnished with other reinforcing elements which are not resistant to bending. The steel sections or profiles can be bent transversely to the plane of the reinforcing elements so that curved reinforcing elements are produced. If necessary the steel section or profile can be applied to the reinforcing element only at the construction site.

It has previously been proposed to provide a reinforcing element, which is at the same time usable as lost shuttering, having several longitudinal ribs consisting of rod-like reinforcing steel which are connected through strip-like cross ribs arranged parallel to one another, which cross ribs are bent outwardly perpendicular to the plane of the plate alternately in the one and other direction and are secured to the rod-like reinforcing steel. According to a further feature of the present invention such a reinforcing element is provided with a steel section, serving as the supporting element resistant to bending, arranged parallel to the longitudinal ribs and connected with the ends of the cross-ribs. The production of such a reinforcing element is particularly simple since the cross ribs can be fastened to the steel section in the same way as to the longitudinal ribs. The reinforcing element according to the earlier proposal retains in this manner all the properties according to the invention.

The steel section serving as supporting element resistant to bending has preferably a rectangular crosssection and is arranged with its narrow sides parallel to the plane of the reinforcing element. In this way there is attainedwith minimum expenditure of material a maximum resistance to bending transversely to the plane of the reinforcing element.

' When using a reinforcing element according to the above-mentioned earlier proposal the cross ribs can be secured with their ends on a narrow side of the steel section of rectangular cross-section. They can however also be secured on a broad side of the steel section of rectangular cross-section. In the first case the rectangular steel section projects only on one side from the plane of the reinforcing element, whilst in the second case it projects on both sides from this plane. The first or second case may be more advantageous according to the intended use of the reinforcing element.

Two contiguous reinforcing elements with their supporting elements resistant to bending can be combined with one another, for example in the simplest case through mutual winding of both bearing elements with wire. According to a further embodiment of the invention, however, the supporting element resistant to bending is provided with fastening devices for connection of two contiguous reinforcing elements. This can, for example, be by bores for screws or other connecting elements such as pins tensioned by wedges. The connecting elements can be recovered after the hardening of the concrete if the fastening devices lie outside the concrete.

Another preferred embodiment of the invention is characterised in that the supporting element resistant to bending is arranged displayed in the longitudinal direction over a part of its length in relation to the corresponding edge of the reinforcing element. In this case not only those reinforcing elements whose supporting elements resistant to bending are longitudinally contiguous can be readily connected with one another, but also those whose supporting elements resistant to bending are laterally contiguous, without additional securing devices such as fish plates being required. Four such reinforcing elements can be located in relation to each other in such a way that in two reinforcing elements with laterally contiguous supporting elements, the'supporting elements are arranged displaced in the same direction and in two reinforcing elements having their supporting elements longitudinally contiguous the bearing elements are arranged displaced in the opposed direction. Accordingly this gives an overlapping of the lateral contiguous positions of the supporting elements through other supporting elements, so that a mutual connection of all supporting elements is possible in the same way as with purely longitudinally contiguous supporting elements.

BRIEF DESCRIPTION OF THE DRAWINGS FIG. 1 shows a plan view of a plate-shaped reinforcing element with side supporting elements,

FIG. 2 shows a side view of a reinforcing element according to FIG. 1 but with curved supporting elements,

FIGS. 3 and 4 show sectional views through different embodiments of reinforcing elements according to the invention in the zone of their supporting elements and FIG. 5 shows the connection positions of four reinforcing elements according to a further embodiment of the invention.

DESCRIPTION OF THE PREFERRED EMBODIMENTS FIG. I shows a plate-shaped reinforcing element which can be used as lost shuttering and has longitudinal ribs I of reinforcing steel and cross ribs 2 and 3 consisting of continuous steel strips.

The cross ribs 2 are all bent out between the longitudinal ribs 1 in one direction perpendicular to the plane of the plate whilst the cross ribs 3 are all bent out perpendicular to the plane of the plate in the other direction. The cross ribs 2 and 3 are all bent out between the longitudinal ribs 1 in one direction perpendicular to the plane of the plate whilst the cross ribs 3 are all bent out perpendicular to the plane of the plate in the other direction. The cross ribs 2 and 3 are all fastened to the longitudinal ribs 1 on the same side. The connection between the longitudinal ribs I and the cross ribs 2 or 3 is produced by spot welding. Spot welding is advantageous for the connection insofar as no structural alterations substantially affecting the tenacity in the longitudinal ribs I are to be anticipated.

A clearance of at least 2 millimetres is allowed between the cross ribs 2 and 3 so that in the overlapping locating of the plates the curved cross ribs 2 or 3 can interfit with a certain tolerance. The rod-like longitudinal ribs project beyond the plate edges to about 30 to 40 times their diameter in order to make possible a troublefree connection between neighbouring plates.

At two oppositely lying edges the reinforcing element has in place of longitudinal ribs I a rectangular profile or section 4, the narrow sides of which are arranged parallel to the plane of the plate. All cross ribs 2 and 3 are preferably welded at their ends with the rectangular profile 4 in the same way as with the longitudinal ribs 1.

One possible type of fastening of the cross ribs 2 and 3 on one of the rectangular profiles or sections 4 is illustrated in FIG. 2. The rectangular profile or section 4 is here curved transversely to the plane of the plate so that the reinforcing element is curved and can for example be used for reinforcement of tunnel arches. The rectangular section 4 can also be curved in any other manner transversely to the plane of the plate and obviously can also be straight, according to the use to which the reinforcing element is to be put. The rectangular section 4 has bores 5 for the passage of fastening elements with the help of which two contiguous reinforcing elements can be connected with one another.

FIG. 3 shows in section one of the edges of the reinforcing element according to FIGS. 1 and 2. The cross ribs 2 and 3 are welded in the same manner to the narrow side of the rectangular section as to the longitudinal ribs 1.

The cross ribs 2 and 3 can also be secured to the broad sides of the rectangular section. One example of this is shown in FIG. 4 in which the rectangular section indicated by reference numeral 4, in contrast with the rectangular section 4, has in cross section an enlarged broad side. The cross ribs 2 and 3 are welded to one broad side of the rectangular profile 4. The cross ribs 2 and 3 are in the region of the rectangular profile 4 bent out in a plane perpendicular to the plane of the plate, and in particular in further continuance of the existing curving of the cross ribs 2 and 3. It would however be possible so to bend the cross ribs 2 and 3 in the region of the rectangular section 4 that their ends show an opposite direction to the direction illustrated in FIG. 4. The rectangular section 4 projects in the embodiment illustrated in FIG. 4 on both sides beyond the plane of the plate. It can accordingly be provided on both sides with bores S and S. A connection of several plate-shaped reinforcing elements is thus possible on both sides of the plane of the plate, according to which side is most accessible.

The connection of two reinforcing elements which have contiguous rectangular sections 4 or 4' has already been described. The connection of two reinforcing elements with contiguous sides not provided with rectangular sections 4 and 4', can take place for example as follows in that the laterally contiguous rectangular sections 4 or 4 are connected by fish plates overlapping both rectangular sections 4 or 4', the fish plates being screwed onto the rectangular sections 4 or 4'.

FIG. 5 shows one embodiment of the invention in which the use of fish plates is unnecessary. FIG. 5 shows four contiguous reinforcing elements ll, l2, l3 and 14, connected with one another, each having in the region of the connecting positions a rectangular section 21 or 22 or 23 or 24. The rectangular sections 21, 22, 23 and 24 do not extend exactly over the length of the associated edge of the reinforcing elements 11, I2, 13 and 14 but are arranged displaced by the distance x, that is to say, one end juts out for the distance x" over the corresponding corner of the reinforcing element and the other end stands back by the distance x in relation to the corresponding corner. In FIG. 5 only one corner of each of the four reinforcing elements 11 to 14 is illustrated. FlGy-S shows an assembly with an overlapping of the two rectangular sections 22 and 23 at the corners of the associated reinforcement elements 12 and 13. By means of at least three connecting elements 6, for example screws, all four reinforcing elements ll to 14 can be connected with one another without further connecting elements such as fish plates being necessary. Only at the ends, limited by the rectangular sections, of reinforcing constructions consisting of one or more reinforcing elements is a mutual connection of the laterally contiguous rectangular sections necessary with additional connecting elements.

1 claim:

1. A plate-like structural element for concrete structures, utilizable as a lost shuttering and as reinforcement, which comprises a plurality of reinforcing steel rods arranged as spaced apart parallel longitudinal rods in planar form, and a plurality of strip-like cross-ribs, means connecting said crossribs to said longitudinal rods at one side thereof only, the cross-ribs being arranged parallel to oneanother and being bent between adjacent rods to form a single half loop between adjacent rods, said half loops lying in a plane perpendicular to the plane of the assembled rods, the said half loops in each cross-rib lying in the same direction with the half loops of adjacent cross-ribs lying in opposite direction so that two offset contiguous half loops of adjacent cross-ribs form a single complete loop, said rods being disposed exteriorly of said complete loops, and said complete loops being adapted to receive concrete with the full lengths of said reinforcing steel rods embedded in the concrete outside of the loops, and steel sections resistant to bending and secured at least to one of the edges of the structural element.

2. A plate-like structural element according to claim 1, wherein saidsteel sections resistant to bending are arranged parallel to the longitudinal steel robs and are connected with the ends of the cross ribs.

3. A plate-like structural element according to claim 1, wherein said steel section has a rectangular crosssection and is secured with its narrow sides parallel to the plane of the structural element.

4. A plate-like structural element according to claim 3, wherein the cross-ribs are fastened with their ends on a narrow side of said rectangular steel section.

5. A plate-like structural element according to claim 3, wherein the cross-ribs are fastened with their ends on a broad side of said rectangular steel section.

6. A plate-like structural element according to claim 3, wherein said steel section has a fastening device for connection of two contiguous structural elements.

7. A plate-like structural element according to claim 3, wherein said steel section is secured displaced in its longitudinal direction for a part of its length in relation to the associated edge of the structural element. 

1. A plate-like stRuctural element for concrete structures, utilizable as a lost shuttering and as reinforcement, which comprises a plurality of reinforcing steel rods arranged as spaced apart parallel longitudinal rods in planar form, and a plurality of strip-like cross-ribs, means connecting said crossribs to said longitudinal rods at one side thereof only, the cross-ribs being arranged parallel to one another and being bent between adjacent rods to form a single half loop between adjacent rods, said half loops lying in a plane perpendicular to the plane of the assembled rods, the said half loops in each cross-rib lying in the same direction with the half loops of adjacent cross-ribs lying in opposite direction so that two offset contiguous half loops of adjacent cross-ribs form a single complete loop, said rods being disposed exteriorly of said complete loops, and said complete loops being adapted to receive concrete with the full lengths of said reinforcing steel rods embedded in the concrete outside of the loops, and steel sections resistant to bending and secured at least to one of the edges of the structural element.
 2. A plate-like structural element according to claim 1, wherein said steel sections resistant to bending are arranged parallel to the longitudinal steel robs and are connected with the ends of the cross ribs.
 3. A plate-like structural element according to claim 1, wherein said steel section has a rectangular cross-section and is secured with its narrow sides parallel to the plane of the structural element.
 4. A plate-like structural element according to claim 3, wherein the cross-ribs are fastened with their ends on a narrow side of said rectangular steel section.
 5. A plate-like structural element according to claim 3, wherein the cross-ribs are fastened with their ends on a broad side of said rectangular steel section.
 6. A plate-like structural element according to claim 3, wherein said steel section has a fastening device for connection of two contiguous structural elements.
 7. A plate-like structural element according to claim 3, wherein said steel section is secured displaced in its longitudinal direction for a part of its length in relation to the associated edge of the structural element. 